Internal-combustion engine.



S. BARLOW.

INTERNAL COMBUSTION ENGINE.

APPLICATION FILED Aue.31. 1915.

1,1 88,607. Patented une 27, 1916.

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awomtoa Sign/Zara arlam S. BA'RLOW.

INTERNAL COMBUSTION ENGINE.

APPLICATION FILED AUG-31,19I5. 1,1 07, Patented June 27,1916.

2 SHEETS-SHEIZT 2.

l lulllll STEPHAN BABLOW, OF MINNEAPOLIS, MINNESOTA.

mrnima'rrcomnusrron ENGINE.

. Specification of Letters Patent.

Patented June 27, 1916.

Application filed August 31, 1915. Serial No. 48,250.

exhaust valve is open for scavenging purposes and also for supplying air to produce an explosive mixture in the engine cylinder,

together with means for proportionately varying the periods of time during-which the inlet and exhaust valves remain open, thereby economizing in the consumption of fuel, enabling the engine to be adjusted by cam mechanism to suit different loads imposed thereon, the latter being accomplished by means of a singlemanually operated device preferably in the form of a hand lever.

With the above and other objects in view, the invention consists in the novel construction, combination and arrangement of parts, as herein described, illustrated and claimed.

In the accompanying drawings :Figure 1 is a vertical sectional view through a single cylinder two cycle engine embodying the present invention, some of the parts being shown in elevation. Fig. 2 is a section taken at right angles to Fig. 1 and also showing certain parts in elevation. Fig. 3 is a detail perspective view of one of the stepped cams.

Referring to the drawings 1 designates the cylinder of a two cycle internal combustion engine, 2 the combustion chamber thereof, 3 the valve chamber, 4 the piston, 5 the crank shaft and 6 the connecting rod.

7 designates the exhaust valve, 8 the exhaust valve spring, 9 the valve stem and 10 the push rod, all of the parts hereinabove referred to being of the usual construction and arrangement, 11 designating. the usual two-part crank case in which the crank shaft 5 is journaled.

In carrying out the present invention, instead of the usual puppet intake valve, I employ a slidable piston valve 12 which ;pens and closes a port 13 at the discharge end of a gasolene feed pipe 14 which extends from a gasolene supply tank 15 preferably located at such elevation as to provide for the necessary flow of gasolene to insure the passage of the same into the combustion chamber of the cylinder.

The valve 12 like the valve 7 is provided with a valve stem 16 and the valve normally held closed by means of a spring 17, 18 designating a push rod which cooperates with the valve stem 16 to open the valve 12.

On the cam shaft 19 are two similar but reversely disposed cams 20 one of which is shown in detail in Fig. 3. Each of said cams has a stepped working face, varying from a relatively narrow portion 22 to a relatively wide or circumferentially elongated portion 23 while between the shortest and longest working faces of the cam there are numerous steps 24 gradually varying in length. Each of the push rods 10 and 18 is shown as provided at its lower extremity with a roller 25 cooperating with the respec-' tive cam as shown in Fig. 2.

I provide means for shifting the cams 20 across the contacting faces of the rollers 25, the means illustrated in the drawings consisting of a hand lever 26 fulcrumed at 27 on an arm or bracket 28 fastened to the engine base, the lever 26 being connected by a link 29 to the shaft 19 by means of a swiveled connection 30 thus enabling the operator to shift both of the cams 20 simultaneously in one direction or the other. When the cams 20 are shifted in one direction the period of time during which the intake valve 12 remains open is increased,

for example, while the time during which the exhaust valve remains open is decreased. By moving the cams 20 in the opposite direction, the reverse condition takes place or, in other words, the intake valve remains open for a shorter period of time while the exhaust valve remains open for a greater length of time. a

In .conjunction with the valve mechanism and timin means therefor, I employ a blower or an the casing of whichis represented at 31, said fan being driven by a belt 32 from the crank shaft 5 and the discharge pipe 33 from said fan or blower entering the combustion chamber through the port 34 which is near the inner limit of movement of the piston 4 but which is opened chamber for the double purpose of scavenging the burned gases from the cylinder and introducing a charge of fresh air just before the exhaust valve closes. Almost at the same instant the intake valve 12 opens allowing raw gasolene to enter the combustion chamber. This all takes place while the piston 4c is near the inner end of its movement. Then as the piston moves toward the cylinder head, the combined air and gasolene are caused to be mixed and compressed followed byra spark from a plug or igniter just as the piston a reaches the outward limit of its movement. I

It will be understood from the foregoing description, taken in connection with the accompanying drawings, that the periods of time during which the intake and exhaust valves remain open may be varied to any desired extent by a simple movement of the lever 26 in one direction or the other causing the rollers 25 to rise upon or descend from higher steps of the cams 20, one of the rollers 25' moving upwardly with respect to the steps of the cam as the other roller 25 moves downwardly in the same direction. In this way the mixture'may be varied together with the power of the impulses obtained from the explosions and-when the engine is traveling under a light load, a very material saving of gasolene or other liquid fuel may be efl'ect'ed. Coupled with this feature of the engine and working in conjunction and supplemental relation thereto is the means for forcing air into the combustion chamber not only for thepurpose of forcing out the burned gases therefrom but for the additional purpose of supplying the necessary air in accordance with the speed of the engine for producin in conjunction. with the raw gasolene an iective explosive mixture, 7

What I claim is v 1. In an internal combustion engine, the combination with an intake valve and an exhaust valve, of stream shaft,'cam's thereon for periodically opening and closing said valves, said cams having stepped faces, the steps of which are progressively elongated circumferentially of the cam, a gasolene feed pipe controlled directly by said intake valve,'and means for forcing air into the base of the combustion chamber, the engine piston serving as the controlling means for said air at the point where it enters the combustion chamber. 1

2. In an internal com-bustion engine, the

combination with an intake valve and an exhaust valve, of a cam shaft, cams thereon for periodically opening and closing said valves, said cams having stepped faces, the steps of which are progressively elongated circumferentially of the cam, a gasolene feed pipe controlled directly by said intake valve, and means driven by the crank shaft for forcing air into the base of the combustion chamber in proportion to the engine speed, the engine piston serving as the controlling means for said air at the point where it enters the combustion chamber. a

In testimony whereof I aifix my signature in presence of two witnesses.

STEPHAN 'BARLO. Witnesses:

CLIFFORD E. BRADLEY, JOHN J. Gun. 

